Java execution .exe File

Java executes the .exe file. Here, Java calls g ++ to compile a program.

(My g ++ compiler and programs are in the directory H:/bin/GCC/bin)

Let's first look at the program:

Package Wen. hui; </P> <p> Import Java. io. bufferedreader; <br/> Import Java. io. inputstream; <br/> Import Java. io. inputstreamreader; </P> <p> public class testexec {</P> <p> Public static void main (string [] ARGs) {</P> <p> testexec javaexec = new testexec (); <br/> javaexec. testprocess (); <br/>}</P> <p> Public void testprocess () {<br/> try {</P> <p> string Path = "H: // bin // GCC // bin //"; <br/> string command = path + "G + +-O "+ path +" test.exe "+ path +" test. C "; <br/> Process = runtime.getruntime(cmd.exe C (command ); </P> <p>/* <br/> * testinputstream errorstream = new testinputstream (Process <br/> *. geterrorstream (); errorstream. start (); <br/> */</P> <p> string line = NULL; </P> <p> // get the process's errorstream <br/> inputstream errorstream = process. geterrorstream (); <br/> bufferedreader reader = new buffere Dreader (New inputstreamreader (errorstream); </P> <p> system. out. println ("----------------- error informaiton ------"); <br/> while (line = reader. readline ())! = NULL) {<br/> system. out. println (line); <br/>}< br/> system. out. println ("--------------- error informaiton ------/N"); </P> <p> int exitvalue = process. waitfor (); <br/> system. out. println ("Return Value:" + exitvalue); <br/> reader. close (); <br/> errorstream. close (); <br/> process. destroy (); </P> <p >}catch (exception e) {<br/> system. out. println ("exception .... "); <br/>}</P> <p >}< br/>

Here is only a demonstration. In actual use, absolute paths should not be used ....

Now let's explain the above program,

In fact, it is very simple. First, write a command, such as G ++ to compile the. C program. The command is: G ++-O test.exe test. c

Runtime. getruntime,

Then call its exec (CMD) method, which returns a process Process

You can see from the process API that process has only a few methods, but it is very useful as follows:

abstract  void	destroy() Kill the child process.
abstract  int	exitValue() Returns the export value of the sub-process.
abstract  InputStream	getErrorStream() Obtain the error stream of the sub-process.
abstract  InputStream	getInputStream() Obtain the input stream of the sub-process.
abstract  OutputStream	getOutputStream() Obtain the output stream of the sub-process.
abstract  int	waitFor() Cause the current thread to wait. If necessary, wait untilProcessThe process indicated by the object has been terminated.

Here, only the information is read from the error stream. If the compilation is incorrect (as can be seen from the return value), the error information will be displayed...